Derivatives having a 2,3-dihydrobenzofuran ring have been reported to have various pharmacological activities and an industrially advantageous process for synthesizing them has been widely sought. Methods for constructing a 2,3-dihydrobenzofuran ring include methods described, for example, in JP-A 5-194466, EP-A-483772, JP-A 5-140142 and WO98/08842. Many of compounds in which a substituted amino group is introduced into the 5-potision on a 2,3-dihydrobenzofuran ring have useful physiological activity and therefore they are important.
In order to introduce a substituted amino group into the 5-position on a 2,3-dihydrobenzofuran ring, as described in WO 00/34262, a method of constructing 2,3-dihydrobenzofuran using as starting material a phenol derivative in which a substituted amino group has been previously introduced into the desired position, and a method of synthesizing the desired compound by nitration or nitrosation of 2,3-dihydrobenzofuran in which the 5-position is not substituted followed by reduction reaction are known. In view of usefulness of 2,3-dihydrobenzofuran compounds, there is a need for provision of a process with high yield under milder reaction conditions, which is suitable for industrial production of these compounds.